It is pretty dire. Even if they beat Argentina, they need to get lucky with the tie-breaker.
Here are the possible tie scenarios and how Canada finishes in each (none of these four teams play each other again, so these tie-breakers will not change).

a) A two-way tie with Mexico, Canada wins.
b) A two-way tie with Venezuela, Canada loses.
c) A two-way tie with Dominican, Canada loses.
d) A three-way tie with Mexico and Venezuela, Canada is first out of those three.
e) A three-way tie with Mexico and Dominican, Canada is first out of those three.
f) A three-way tie with Venezuela and Dominican, Canada is last out of those three.
g) A four-way tie with Venezuela, Dominican, and Mexico, Canada finishes last out of those four.

There are zero scenarios where Canada can lose tomorrow and still advance.
If they win, there are sixteen possible outcome combinations for remaining games. By my count, 9 of those combinations result in them being eliminated, 7 result in them advancing (highlighted in red). Short answer is that other than their own game, the game that's most important is Puerto Rico vs. Mexico. If Puerto Rico wins that, Canada advances in 6 of the 8 scenarios.

Is there another qualifying tournament for Spain 2014 next year for teams from various regions of the world that finished just short of qualifying, which in FIBA Americas case, the fifth and sixth place teams?

Is there another qualifying tournament for Spain 2014 next year for teams from various regions of the world that finished just short of qualifying, which in FIBA Americas case, the fifth and sixth place teams?

Nope, just four wildcard spots. You pay $500,000 to FIBA, tell them how great you are, then they pick the teams they want based on some mysterious criteria.